Benzoquinone derivatives, which undergo reversible two-electron redox reactions, should afford high capacity as positive electrode materials for rechargeable batteries. Although some benzoquinones have been reported as cathode active materials, their low cycle-life performance is a drawback. We prepared benzoquinones bearing alkyl groups with various degrees of bulkiness to investigate the relationship between the steric effects of the substituents on the benzoquinone skeleton and the battery performance. The introduction of bulky substituents, especially a tert-butyl group, on the skeleton significantly improved the cyclability.